1. Field of the Invention
The present invention relates to a mobile radio terminal employed in a mobile communication system, such as a cellular telephone and the like.
2. Description of the Related Art
A known cellular telephone has a roaming function of establishing communications via a radio base station of a carrier other than other than the carrier with which the user is under contract. If the cellular telephone cannot find the carrier under contract outside the service area, the cellular telephone executes roaming to the other carriers to obtain a cellular telephone service (cf., for example, JP-A No. 2000-13846 (KOKAI)).
However, the cellular telephone has functions which cannot obtain services during the roaming. Thus a problem arises that the cellular telephone establishes communications to obtain the service via radio base stations though the cellular telephone cannot obtain the service and unnecessary communication expenses need to be paid.
After buying a cellular telephone, the user adds functions by arbitrarily installing software such as a Java™ application and the like. However, as such application software is often created without considering roaming, the above problem occurs frequently.
In the conventional mobile radio terminal, although some functions cannot obtain services during the roaming, communications to obtain the services are established and unnecessary communication expenses need to be paid.